


Fox and Bunny

by SoloShikigami



Category: Undertale (Video Game)
Genre: Bondage, Breeding, Kemonomimi, Knotting, M/M, Mating Cycles/In Heat, Underfell Sans (Undertale), Underswap Sans (Undertale)
Language: English
Status: Completed
Published: 2020-05-12
Updated: 2020-05-12
Packaged: 2021-03-02 20:33:34
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,185
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24152869
Author URL: https://archiveofourown.org/users/SoloShikigami/pseuds/SoloShikigami
Summary: Bunny!Red comes home to find Fox!Blue in heat.
Relationships: Sans/Sans (Undertale)
Comments: 3
Kudos: 103





	Fox and Bunny

**Author's Note:**

> Written for Lycovore in November, 2018!

Red knew he was in trouble the moment he entered Blue’s room, his long ears twitching in alertness. He knew he was in big trouble when the door lock clicked, making his ears press against his back. He wasn’t quite sure what kind of trouble when he was pinned with the bigger creature looming over him and looking at him as if he were a meal to be devoured.

Maybe this time, he was.

“B-B-Blue, what’re you-?!” Red began to stammer.

That’s when the smell hit him like a brick wall; it didn’t quite agree with his senses, smelling a bit like wet fur mixed with musk, but that was alongside the scent that was all Blue’s own, which made Red swoon. Even now, the smell was stronger, almost instinctually relaxing him like a spell. He felt his eyes roll slightly, but then he was quickly brought back to reality when Blue made a pleased rumbling sound in his chest and ground against him.

“Blue, wait, I, I’m not,” Red began to protest.

“You smell so good today, Red” Blue murmured, nuzzling along Red’s neck. “I’d like to taste you.”

Red shivered; he wasn’t sure if Blue meant it in a predatory way or a predatorily sexy way, but he nodded, leaning his head back to expose his neck and deciding the chance was worth it. Blue grinned, flashing bright teeth and sharpened canines before he bent to lick along his bones. Red’s legs kicked slightly as Blue touched upon every sensitive bit of cartilage his agile tongue could reach.

“I want you real bad, Red,” Blue said, his voice deeper and husky with lust. “I need you.”

He pressed his body down on Red again, making him well aware of his desire and oddly assuring Red that he wasn’t going to eat him.

Not like that, anyway.

Blue’s scent was making Red dizzy, stirring up something deep inside his soul. His magic began to form before he could even think of an answer.

“Mmm, I can smell it, Red, I can smell you,” Blue murmured. “I’d like to have a taste.”

Red panted, squirming more, part of him wanting to get away, but another part of him just wanting to rub more against his lover.

“Blue, please, just,” Red whined, wanting the decision to be taken out of his hands.

Blue chuckled before making quick work of Red’s shorts and bending down to breath in the scent of his dampening magic.

“I love the way you smell, Red, but I also love how you taste,” Blue said as he leaned in.

“Ah! Mmmm, Blue! Fuck!” Red cried, his hands scrambling on the top of his head, nearly grabbing his ears.

Blue growled, pressing his tongue deeper, wrapping his arms around Red’s legs to keep him still - or at least, his lower half still. Red’s ears flopped around as he tossed his head, his hands switching between scratching at the top of Blue’s head, scratching at the floor, and pressing over his mouth to keep his cries quiet.

“No,” Blue growled after hearing a muffled shout, suddenly stopping and gripping Red’s wrists. “I want to hear you.”

Red was in a daze and didn’t realize what Blue was doing until it was too late; the fox had turned him over onto his belly, his legs adjusted so that his knees were bent, and his hips were up in the air, and his arms were gently but firmly pulled behind his back. One wrist was gently taken, a soft cloth (it must have been Blue’s bandana), was wrapped around it and Red’s arm was bound to one leg. While he tested the bond, there was the sound of ripping and another strip of cloth slipped around the bones of his other wrist (“I suppose there goes my shorts,” Red thought distantly), and soon that one was bound to his other leg. The position left him unable to move much and his entrances exposed. Blue leaned over him, a hand on the back of his neck, pressing him into the carpeted floor.

“You look like you’re ready to have an apple stuffed into your mouth and be popped into an oven,” Blue said.

A flash of fear crossed Red’s eyes and he tried to turn his head to look at Blue, trying to figure out how serious he was, but a chuckle and a gentle kiss pressed to his cheekbone reassured him.

“I have to say, though, I enjoy my meals raw.”

Red whimpered as Blue retreated, fighting against the bonds, for a moment before Blue’s tongue was shoved back into him, and his hands held Red firmly to keep him from moving.

Red tried to contain his cries of pleasure, but he found it damn near impossible; Blue knew him too well, and even in his time of being ruled by his most primal of instincts, he knew how to drive Red insane, quickly bringing him to orgasm.

“Not done yet, my sweet little bunny,” Blue all but purred after he finished lapping up Red’s first release. “I’m going to make you my mate, Red, give you the means to carry my litter, mmm, can’t begin to tell you how proud I’m going to be to watch you give birth to our babies.”

“B-ba-babies? Mate? But, Blue, we, I-!” Red stammered, caught between being more turned on than he ever had been in his entire life, and comprehending what Blue was asking - telling - him.

“Shh, shh, it’ll be okay, Red, I’ll protect you,” Blue murmured, rubbing his cock against Red as he lapped at the back of his neck. “No one is going to mess with my mate, just you see if anyone tries to.”

Red wriggled and whimpered as he felt the head of Blue’s cock catch on the edge of his entrance, his mind flashing between wanting nothing more than to mate with this heat-driven fox that he loved, and the logical part of him that screamed that what they wanted was impossible.

But all thoughts were driven out a moment later. Red arched and nearly screamed as he was penetrated, Blue feeling bigger than usual (or maybe it was just the position he was in?) and was a panting mess by the time Blue stopped moving. Red could feel him shuddering above him in pleasure, letting out a slow, low moan, enjoying the feeling of being inside of the monster he loved.

“Red,” Blue breathed. “I, I don’t have much control left, b-but, I, I can stop, if you want me to.”

“You’re already inside me, asshole,” Red ground out, knowing fully well that he would be amused by Blue’s statement if he wasn’t getting lost in a haze of ecstasy.

“I, I know, but still,” Blue took a deep breath and let it out slowly, shakily, his body shifting and drawing out a whimper from Red. “I, I’m sorry, I should have asked first, but, this just came on, and I love you, and I-!”

“For fuck’s sake you dumb fox, fuck me!” Red snarled, trying to move underneath him. “Yeah, ya shoulda asked _first,_ ya dumb shit, but now I’m turned on, horny as hell, and fuck yeah I’ll have your babies! Now stop being such a wussy alpha male and fuck me into the floor!”

Blue blinked in surprise as he listened to Red’s tirade. It didn’t take more than another second before he was leaning over him again in the attitude he had before, nuzzling the back of his neck.

“Thank you, I love you, Red,” Blue murmured before opening his mouth and sinking sharpened teeth into the neck of the rabbit, just hard enough to mark him.

The rush of fear that ran through Red was from instinct, but as Blue began to move inside of him, another instinct took over, lust returning in a rush as the fear drained out. Blue fucked him slowly, the drag of his thick cock along his walls, feeling every inch of him was turning Red’s mind into mush. A string of swears, moans, and desperate pleas were spilling out of Red’s mouth.

As Blue fucked Red gently, slowly, his hands wandered over every inch of the bunny’s body that he could – and him being so much smaller than himself, that wasn’t particularly difficult – and he made sure to linger on the spots that Red liked.

“So sexy, so hot, I love you so much,” Blue murmured.

Red only tried to bury his face in the carpet, tears of desperation beginning to fall.

Blue’s own body was beginning to reach its own peak, as he could feel the knot forming at the base of his cock. He knew it was time to finish this, bring his mate the highest pleasure he could before giving him the means to carry their offspring.

But dammit he wanted to look into his eyes for this one.

It pained Blue to pull out, and Red wriggled and nearly screamed in protest, but he was quickly turned over onto his back and Blue was inside of him in one smooth motion.

“I want to see you,” Blue said, thrusting in faster now. “I want to watch your face as I mate you, claim you, make you mine.”

Red fought his bonds, wanting to wrap himself around Blue, bring him in as close as possible to feel every bit of him that he could, but there was something very hot about not being able to, knowing that his pleasure was at Blue’s mercy.

“Please, Blue, please, I’m gonna die,” Red whined, tears freely spilling from his eye-sockets.

“As if I would allow that,” Blue said with a small laugh, leaning down to lap at Red’s face, licking up the tears, and kissing him deeply. “Don’t hold back now, love, I want to hear you scream my name.”

Blue thrust in particularly deep and hard, making Red cry out, but then he stopped moving, which made Red begin to question. Blue made another rumbling sound in his chest, his hands reaching down one at a time to free Red from his bonds, guiding his legs to wrap around his middle, and Red’s arms began wrapping around his shoulders.

“B-Blue? W-what is- AHHH!”

It felt like Blue was growing thicker while deep inside of him.

“Shh, shh, it’s my knot, you’ll be okay, just hang on,” Blue whispered, holding onto Red tightly, moving to kiss and lick him around his face and neck.

“Fuck, Blue, Blue!” Red cried out as the knot reached its full thickness, Blue pushing forward a little to make sure he was properly seated.

Red thrashed under him, which hurt a little, but Blue’s cock also pulsed inside of him, bringing more pleasure. Blue reached one hand between then and began to rub at Red’s clit, murmuring more praises into the side of his skull.

“Cum for me, Red, cum for me,” Blue murmured.

Red did indeed scream Blue’s name as he came a second time, Blue growled, biting Red’s neck again as he pushed into him again, finally reaching his own climax, his hot magic spilled deep inside of Red.

“Fuck, fuck, it’s so much, I, I- gah!” Red stammered, voice strained.

“Mweh, did, did you just cum again?” Blue asked. He laughed when Red didn’t answer. “Such a good boy.”

Waves upon waves of ecstasy washed over them both, leaving them panting as Blue’s magic calmed; the knot didn’t dissipate just yet, so he carefully wrapped his arms around Red, lifting him off the ground carefully and slowly moving him into his lap. Blue adjusted so he was sitting against the wall, the bunny quivering in his embrace.

“Are you okay?” Blue asked, petting the long bunny ears.

“Y-yeah, I t-th-think so,” Red said shakily. “Wh-what happens n-now?”

“My knot will take some time to go away, it’s to assure that I properly impregnate you.”

“But aren’t we going to do this, like, a million times over the next few days? That’s how us bunnies do it.”

“We could, but this probably will only happen one more time during the cycle.”

“Oh.”

“You sound disappointed.”

“Shut it,” Red wriggled, trying to become more comfortable and pretty much failing. “Uhm, so, did you mean it that you’ll protect me if I’m pregnant?”

“Red, I’ll protect you no matter what,” Blue reached up to cup Red’s face, leaning in to kiss him deeply. “Being mates isn’t just about raising our litter. I will protect you, I will always be with you.”

Red looked into Blue’s eyes, searching for any hint of insincerity, and of course, finding absolutely none. He leaned forward to kiss Blue.

“I’ll protect you, too,” Red said.

“Mweh, heh, heh, not with a belly full of pups and kits,” Blue chuckled.

Red growled. “Fuck you.”

Blue smirked and carefully rolled his hips up to remind Red of his position. Red gave a small yelp, glared at Blue, but then huffed and leaned against him, letting Blue continue to pet him soothingly as he continued to make amused noises at his lover, his mate.

**Author's Note:**

> Like what you read? Please check out my social media for more fun!  
> [ My Tumblr](https://soloshikigami.tumblr.com/)  
> [ My Twitter](https://twitter.com/SoloShikigami)


End file.
